(1) Field of the Invention
The present invention relates to an image signal processing apparatus, an image display device, and an image signal processing method, and relates particularly to techniques to suitably reduce crosstalk, which poses a problem when images are displayed.
(2) Description of the Related Art
Patent Reference 1 (Japanese Unexamined Patent Application Publication No. 2001-258052) discloses a technique which an image display device uses to cancel out crosstalk between left and right images. According to Patent Reference 1, before a process of crosstalk cancellation, a left-eye image signal and a right-eye image signal are compared in order to extract an image area having a difference therebetween, and then a process of decreasing contrast is performed on the image signals indicating the image area. Subsequently, on the image signals subjected to the process, crosstalk cancellation is performed to cancel predetermined crosstalk between the left and right image signals.
The conventional crosstalk cancellation process disclosed in Patent Reference 1 facilitates improvement of effect of crosstalk cancellation to reduce crosstalk even in approximately black images, where crosstalk tends to be noticeable. Specifically, first, an image region having a large signal level difference is extracted based on difference between left and right image signals in the signal level. Then, the level of an image signal which corresponds to the extracted region and has a higher level than the other image signal is lowered, and the level of the other image signal, which has a lower level, is raised. Contrast between left and right signals is thus suppressed, so that crosstalk is cancelled.
However, this crosstalk cancellation is performed through a predetermined process regardless of characteristics of images. Such crosstalk cancellation may be unsuitable for characteristics of some images.